3. Follow up by S. Refoua

I wrote this to you, but didn't want to bog down your inbox so I didn't send it. but then I realized if I put it into a blog, it's less intrusive. 

On June 7th, 2016 - S. Refoua wrote:

Hi David, 

I want to re-iterate I think you're right. I don't think it's a good idea to get that granular with students. I didn't mean to give the impression I want to teach bartending students this stuff.  But I've been giving shortened descriptions to upper middle class "home bartenders" for a years. For myself, this kind of stuff keeps me motivated and interested in subject matter which otherwise may go stale. Can I just try one more time?

Presumption: Temperature and Dilution are dependent variables of Shaking vs. Stirring. Safe to say everyone agrees about the difference in preference due to these variables.     

My question:

  1. Is the difference in preference observed when adjusting other independent variables* due to: Differences in texture OR Acidic reactions to ethanol?


  1. *Unexplained Observations:
    1.  We know from experience if we're done shaking, and realize we forget the lime/lemon juice, why is it so hard to integrate the lime juice to the post-shaken mixture, re-shake, and have it be as good? If we start over, and don't forget the lime juice, we achieve significantly different results, no? 
    2. In addition, it appears more okay to forget the sugar (i.e. simple syrup), and add it after we are done shaking, yes? 
    3. Lastly, the less acidic the forgotten ingredient, the more okay it is to forget, add post-shaken, and re-shake. (i.e. orange juice, grapefruit juice). 
    4. The above claims are believed true by myself and bartenders I've asked. They are currently assumptions, unless you challenge. 
  2. Problem: 
    1. Considering the above observations, and holding temperature and dilution constant (2009 Cooking Issues, Science of Shaking II), the variance in preference doesn't seem attributable to texture. Why?
      1. You should be able to create the same texture by re-shaking with the addition of acidity to a post-shaken drink.
      2.  There should be no difference in preference when forgetting other non-acidic ingredients (i.e. simple syrup).
      3. There should be no correlation between preference and levels of acidity in forgotten juice (i.e. OJ, Grapefruit).
  3. Research: 
    1. Based on feedback from chemists: 
      1. Weak Acid + Ethanol = some type of Ethyl Ester. 
      2. Any difference in PH levels based on juice (forgotten) vs. (not-forgotten) is due to the above reaction.
      3. The literature on this is curiously absent, but chemists I've asked tend to agree: Esters which could be created if Shaking Condition starts warm, may not be created if Shaking Condition is cold/dilute. 
    2. Based on feedback from several F&B sources:
      1. Differences in small amounts of esters (and PH levels) are known to produce significant differences in preference. 
  4. Consider the following:
    1. In Cooking Issues, Cocktail Science in General, Part 2 of 2: One would get the same differences in preference (i.e. fake shake data) if they plugged in "acidity" data VS. the (current) data measuring texture levels.
    2. However, the opposite is not true for the Unexplained Observation above.  
  5. Valid Study?
    1. It appears no one has considered testing for the acid / ethanol reaction. 
    2. The possible presence of this reaction fits well with all observations in this email.
    3. This alternative explanation, if proven, will be important. 


Shawn RefouaComment